本文将结合作者近日工作中,在ORACLE数据库分页查询时,遇到一个小问题,为大家讲解如何解决Oracle分页查询中排序与效率问题. 原始未分页查询Sql代码如下: select ROWNUM rn, t.id ID, o.name YYB,u.name XM, t.MC from tZDYSX t,tuser u,lborganization o where t.cjr=u.id and u.orgid=o.orgcode and t.gx = 1 order by ID 结果如下: RN I
Question When does the Oracle library for st_shapelib.dll need to be changed? Answer The library is the path for Oracle to locate the external .dll file used by st_geometry functions and operators with Oracle's external process. To identify the st_s
问题描述 以下简写下建的表:create table A (id varchar2(20) ,-------主键num integer);create table B (id numbercount integer);A表与B表在不同的库,我现在登录的是C库,能同时查询到A与B,现在需要更新 A的num 字段为B的count字段,A与B的关系是 A.id = 'b' || B.id .A与B大概有200多W的数据 解决方案 可以尝试用Oracle的Merge语法,效率很高的:Merge into
问题描述 要对比两张表TA和TB: select * from TA a where not exists (select v_key from TB b where a.v_key = b.v_key); select * from TA, (select v_key from TB) c where TA.v_key = c.v_key(+) and c.v_key is null;如果表TA和TB都有大量数据的话,哪个效率会比较高一点? 问题补充:话说能不能顺便稍微解释一下为什么较快或者较